The present invention generally relates to plumbing equipment, and more particularly to problems associated with cleaning a plugged sewage drain line, for example, of the types found in residential and commercial buildings.
If a sewage drain line becomes obstructed in a residential or commercial building, the blockage is typically removed with a clean-out tool, for example, a rod or cable inserted through a clean-out located in the drain line below the obstruction. The clean-out is often, though not necessarily, a branch of a Y-fitting whose other branch is inline with the drain line. A plug is typically installed in the clean-out and must be removed before inserting the clean-out tool. A common problem encountered with drain clean-outs is that as soon as the clean-out plug is removed, any sewage below the obstruction rapidly drains from the drain line as the clean-out plug is being removed, often resulting in a spill that must be cleaned.
U.S. Pat. No. 2,241,560 to Schouler, U.S. Pat. No. 4,159,721 to Horter, U.S. Pat. No. 5,144,699 to Graham, and U.S. Published Patent Application No. 2005/0283890 to Schaaf are each concerned with draining a drain system prior to attempting to remove an obstruction. Schouler discloses a valve between a drain system and a clean-out plug, and through which sewage can drain to a hose. Schaaf discloses a drain valve that, while located downstream of a drain plug, enables a drain system to be drained without removing the plug. Graham discloses a drain hose attached downstream of a valve that operates as a drain plug on a drain system. Horter discloses a drain hose attached downstream from a clean-out plug of a drain system. Horter provides a sleeve adapted to be secured to the end of a clean-out fitting in which the plug is installed, and removal of the plug is performed by inserting one's hand into a glove attached to the opposite end of the sleeve and then grasping and turning the plug with the user's gloved hand. The glove is then removed from the sleeve to permit the insertion of a clean-out tool through the sleeve and into the drain system.
U.S. Pat. No. 2,451,051 to Tubbs discloses a clean-out device and method for removing an obstruction from a drain line without the need to drain the line prior to removing the obstruction. Tubbs' device is intended for use above an obstruction, which results in the device being subject to much if not all of the hydraulic pressure exerted by the sewage above the obstruction. The device is shown attached to an upward-extending branch of a Y-fitting that is installed in a vertical sewer pipe and has a clean-out plug installed at its upper end. The clean-out device includes a cylinder having a lower end adapted to be attached to the upper end of the branch and an upper end with two openings, one of which permits a clean-out tool to be inserted into the cylinder. The device further includes a rod adapted to be attached to the plug with a cotter pin. The clean-out device is intended to be temporarily installed on the branch when required to remove an obstruction in the sewer pipe. In use, the rod is first attached to the plug and the cylinder is installed over the rod and attached to the upper end of the branch, after which the clean-out tool is inserted into the cylinder through the opening in the upper end of the cylinder. During installation of the cylinder onto the branch, the rod is passed through the second of the two openings at the upper end of the cylinder to enable the rod to be operated from outside the cylinder to remove the plug from the branch. Once the plug is removed from the branch and tilted out of the way, the clean-out tool is used to remove the obstruction within the sewer pipe. Thereafter, the sewer pipe can be flushed with water introduced through a faucet mounted to the side of the cylinder. Accordingly, the intent of Tubbs' clean-out device is to prevent any sewage from draining from the drain line prior to and during removal of an obstruction.